03-27671. Airworthiness Directives; Boeing Model 727 Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Boeing Model 727 airplanes. This proposal would require an inspection of the bolts used to attach the forward cone bolt to the engine flange to determine if the attachment bolts are either H-11 steel bolts or cadmium-plated bolts. This proposal would also require replacement of either H-11 steel bolts or cadmium-plated bolts with new corrosion-resistant steel bolts. This action is necessary to prevent undetected cracking of the H-11 bolts or excessive wear of the cadmium-plated bolts, which would compromise the primary load path of the engine support and could result in separation of the engine from the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by December 19, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-273-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2002-NM-273-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2002-NM-273-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-273-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received reports indicating that H-11 steel bolts used to attach the forward cone bolt to the engine flange of Boeing Model 727 airplanes are susceptible to stress corrosion cracking, although no reports of related cracking have been received. Also, the cadmium-plated bolts that were also used in production are not sufficiently wear-resistant for the application. This condition, if not corrected, could compromise the primary load path of the engine support, which could result in separation of the engine from the airplane.

Explanation of Relevant Service Information

The FAA has reviewed and approved Boeing Alert Service Bulletin 727-71A0402, dated January 18, 2001, which describes procedures for inspecting the bolts that are used to attach the forward cone bolt to the engine flange to determine if H-11 steel bolts or cadmium-plated bolts are installed. The service bulletin also describes procedures for replacing H-11 steel bolts or cadmium-plated bolts with corrosion-resistant steel bolts. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously, except as discussed below.

Differences Between Proposed Rule and Service Bulletin

Operators should note that, although Boeing Alert Service Bulletin 727-71A040s, dated January 18, 2001, recommends that the affected bolts be inspected and replaced at the next convenient scheduled maintenance period not to exceed 3,000 flight cycles, this proposal would require that the affected bolts be inspected and replaced within 18 months or 3,000 flight cycles from the effective date of this AD, whichever is earlier.

Cost Impact

There are approximately 1,148 Model 727 series airplanes of the affected design in the worldwide fleet. The FAA estimates that 715 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 3 work hours per airplane to accomplish the proposed inspection, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $139,425, or $195 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations proposed herein would not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Boeing: Docket 2002-NM-273-AD.

Applicability: All Model 727, 727C, 727-100, 727-100C, 727-200, and 727-200F series airplanes, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent undetected cracking of the H-11 steel bolts or cadmium-plated bolts, which would compromise the primary load path of the engine support and could result in separation of the engine from the airplane, accomplish the following:

Inspection and Replacement

(a) Within 18 months or 3,000 flight cycles from the effective date of this AD, whichever is earlier, inspect the bolts that are used to attach the forward cone bolt to the engine flange to determine if they are H-11 steel bolts (part number (P/N ) BACB30GU12-64), cadmium-plated bolts (P/N BACB30LM12-64), or corrosion-resistant bolts (P/N NAS6712E64), per the Accomplishment Instructions of Boeing Alert Service Bulletin 727-71A0402, dated January 18, 2001.

(1) If corrosion-resistant bolts (P/N NAS6712E64) are installed, no further action is required by this paragraph.

(2) If any H-11 steel bolt or cadmium-plated bolt is found, before further flight, replace the bolt with a new corrosion-resistant bolt (P/N NAS6712E64), according to the Accomplishment Instructions in the service bulletin.

Parts Installation

(b) As of the effective date of this AD, no person may install an H-11 steel bolt (P/N BACB30GU12-64) or a cadmium-plated bolt (P/N BACB30LM12-64) to attach the forward cone bolt to the engine flange on any airplane.

Alternative Methods of Compliance

(c) In accordance with 14 CFR 39.19, the Manager, Seattle Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance for this AD.

Issued in Renton, Washington, on October 29, 2003.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.